Web positioner bar



June 1Q, 1969 R.T.OTEPKA ETAL 3,448,907

WEB POSITIONER BAR filed Dec. s, 1966 f sheet` `of 2 'T/ E'. j.

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WEB POSITIONER BAR' Filed Dec. s, 1966 sheet of 2 United States Patent O 3,448,907 WEB POSITIONER BAR Rudolph T. Otepka, Wheaton, and Arthur G. Stout,

Lincolnwood, Ill., assignors to Web Press Engineering, Inc., a corporation of Illinois Filed Dec. 5, 1966, Ser. No. 599,285 Int. Cl. B65h 17/22 U.S. Cl. 226-97 6 Claims ABSTRACT OF THE DISCLOSURE The present invention pertains generally to web supporting apparatus land, more particularly, to improved web supporting .apparatus 'wherein long lengths of a moving web are supported by an air barrier in spaced relationship to a support.

A problem in high speed printing today is the drying of the ink on a moving web as the web leaves the high-speed press in as s hort a time as possible. Ordinarily, the moving web, which may be printed on both sides thereof, is con,- veyed from the printing press, which may be 'a letter press or offset press, to a dryer mechanism wherein heated air is blown against the opposed surfaces of the web to dry the ink thereon. Typically, greater rolls are used to support the relatively long lengths of paper conveyed between the printing press and the dryer. Heretofore, one way to support the moving web in spaced relationship from the surface of the greater roll to prevent smearing of the wet ink was by pin-like projections extending from the roll. Some smearing of the wet ink, however, resulted and this solution was not entirely satisfactory.

Various attempts have been made to provide nozzle means for blowing air against the moving web so as to support the web on an air cushion. Present arrangements have not been found entirely satisfactory for they do not adequately stabilize and remove the flutter from the elongated lengths of rapidly moving web and, accordingly, there is a tendency for the web to brush against the nozzles on one side or the other of the web and thereby smear the wet ink on the web. Nozzles opposed to one another in a common plane have been used, however, the pressure balance between the nozzles is quite critical, and if there should be a variance in pressure on one side or the other, the web Iwould move toward the reduced pressure side and result in contact Yof the surface of the web with a nozzle, thereby smearing the wet ink carried on the surface of the web.

An object of the present invention is to provide improved web positioning mechanism including an elongated housing having a pair of spaced elongated slot-like openings in one side thereof, with the pressurized air discharging from the openings being guided by deiiector means secured to the housing toward one another in converging relationship to provide a pressurized air barrier capable of supporting a moving web in spaced relationship to the housing.

Another object of this invention is to provide web positioning mechanism including a first tubular housing disposed on one side of a moving web and a second tubular housing disposed on the opposite side of the moving web, each housing having a pair of spaced elongated slot-like ICC openings in one side thereof, and deiector means secured to each housing adjacent each slot-like opening for directing the air streams discharging from each opening in a converging manner toward one another so as to provide a pressurized air barrier, the air barrier being 'formed on the tirst tubular housing being oifset from the air barrier formed by the air discharging from the second housing along the line of travel of the web so as to minimize flutter of the moving web. Other objects and ladvantages of the present invention will become more apparent hereinafter.

The specific details of a preferred embodiment of the invention and their mode of functioning will be particularly pointed out in clear, concise and exact terms in conjunction with the accompanying drawings, wherein:

FIG. 1 is ia schematic view of a printing installation incorporating a printing press and dryer mechanism, the installation incorporating web positioning apparatus embodying the present invention;

FIG. 2 is a side view of la web positioning bar incorporating the principles of the present invention;

FIG. 3 is a cross-sectional view of the web positioning bar taken generally along the line 3 3 of FIG. 2;

FIG. 4 is an end View o'f the web positioning bar of FIG. 2; and

FIG. 5 is a bottom view of the web positioning bar.

Referring now to FIG. 1, there is illustrated a printing installation incorporating the web positioning apparatus of the present invention. Material may be printed on both sides of the moving web by a conventional printing press 10 as, lfor example, an offset press or a letter press, and the moving web will then pass through a dryer mechanism 12 having a plurality of banks of nozzles 13 disposed above and below the moving web 14 -for effecting drying of the ink on the opposed surfaces of the fweb. The web then passes over a roller or rollers 16 land may then be guided to suitable cutting equipment wherein the web may be cut to desired sheet form or to a storage roll. It will be understood that it is desired that nothing come in contact with the surface of the web that would tend to smear the ink prior to the time that the ink has been thoroughly dried on the opposed sur-faces of the web.

Web positioning mechanism 11 in accordance Iwith the present invention is provided between the printing press 10 and the dryer 12 to provide desired support for the web so as to stabilize same and remove the Hutter that occurs when an elongated web moves rapidly over a great distance in an unsupported manner. In present equipment, the web may be conducted lat speeds up to 2000 feet per minute. The web positioning mechanism 11 is capable of satisfactorily supporting moving webs traveling at 2000 feet per minute and higher. As shown in FIG. 1, mechanism 11 includes a pair of web positioning bars or pressure bars disposed on opposite sides of the web in offset relationship with respect to the line of travel of the web. Air is discharged sat a high velocity through spaced openings in the bottom of each web positioning bar to form an air barrier capable of supporting the moving web in a firm manner so as to remove the flutter from the moving web and prevent any contact between the moving web and the web positioning bars to obviate any smearing of the moist ink on the web.

Single web positioning bars 20 may be disposed between adjacent banks of nozzles 13 within the dryer 12 to help stabilize the fast moving web 14. Preferably, the rst and last dryers are tilted with respect to a horizontal plane so as to raise the web and then lower the web as it passes through the dryer. The web 14 is offset in the intermediate bank of nozzles from a plane through Web positioning mechanism 11 and the top of roller 16.

Turning now to FIGS. 2-5, there is illustrated a web positioning bar or pressure bar embodying the principles of this invention. Each web positioning bar is comprised of a tubular housing member having defined therein by suitable wall means a pair of chambers 21 and 22. The chambers 21 and 22 are communicated at one end with an inlet conduit 24 that is adapted to be connected to a source of pressurized air. Provided within the inlet conduit 24 is an air splitter or battle mechanism 25 for `dividing the incoming pressurized air equally for ow into the respective chambers 21 and 22.

Formed in one side of the housing are a pair of elongated slot-like openings 28 and 30 that extend substantially the full length of the housing of a pressure bar 20.

Detlector means are secured to the housing for directing the air streams discharging from each opening 28 and 30 toward one another in a converging manner so as to provide a pressurized air barrier capable of Supporting a moving web in a xed relationship with respect to the end of the deector means remote from the housing 20. The dellector means may comprise a generally U-shaped channel-like member 34 suitably connected to one side of the housing 20 between the openings 28 and 30. Secured to the base 34a of the channel-like bracket member 34 by suitable fastening means 36 is a structural plate member 38. The plate member 38 comprises a generally planar base that is adapted to be secured to the bottom 34a of the channel-like structural member 34, up wardly diverging side wall portions 38a and 381; and inwardly turned portions 38C and 38rd. Cooperating with the plate member portions 38a and 38b are plate members 40 and 41. The plate members 40 and 41 include downwardly and inwardly converging portions 40a and 41a which cooperate with the plate member portions 38a and 38b to provide narrow elongated slot-like openings -42 and 44 from which the air may discharge at a high velocity.

In a presently preferred form of the inveniton, the wall members 38a and 38h are disposed at an angle of about 30 with respect to the vertical and the plate member portions 40a and 41a are disposed at an angle of about 45 with respect to a vertical plane. The slot-like openings y42 and 44 are continuous and each has a width of about 0.010 inch. As indicated in FIG. 3, the converging air streams form a region of extremely high turbulence 46 generally triangular in cross-section adjacent the bottom of the deector means, which air barrier is capable of supporting a moving web in spaced relationship to the bottom of the deilector means.

Means are provided for adjusting the size of the elongated slot-like openings 42 and 44. Such adjusting means may comprise means for permitting adjustment of the outermost plate members 40 and 41 toward and away from the innermost plate member portions 38a and 38b. For example, a number of oversized holes 48 and -49 respectively may be provided in the upper flange portions of the plate members 40 and 41. By loosening the retaining screws 50 and 51 which support or secure the side plate members 40 and 41 to the housing 20, the side plate members 40 and 41 may -be moved toward and away from the central plate member 38 to regulate the width of openings 42 and 444.

The housing is elongated and may be made of sucient length so as to accommodate the normal width of webs used with modern printing equipment. It will be understood that the openings 28 and 30 in the bottom of the chambers 21 and 22 of housing 20 are generally coextensive in length to the nozzle-like openings 42 and 44 -in the deector means. In the event that the web positioning mechanism of the present invention is utilized for web widths substantially less than the length of the openings 28 and 30, spacer members may be provided for blanking oit a portion of each end of the slot-like openings 28 and 30. In this manner, the discharge area is reduced and the quantity of air necessary to yield a predetermined air velocity is reduced, thus effecting a saving 4 in the horsepower required to drive the supply fan for providing pressurized air to the housing 20.

Secured to each end of the housing of web positioning bar 20 are angle brackets 60 and 61 (FIGS. 4 and 5). The angle brackets 60 and y61 are provided with elongated openings 62 and 63 -for permitting connection of the web positioning bar 20 to a suitable support member adjacent a dryer mechanism in a printing installation.

It will be apparent to those skilled in the art that in certain applications only one web vpositioning bar will be needed, though it is preferable in the installation shown in FIG. 1 that two web positioning bars be utilized, one offset from the other along the line of web travel, so as to minimize the undesirable utter of the moving web which is unsupported for relatively great lengths, on the order of 16 to 18 feet. For example, to change direction in a moving web Without contacting either side of the web, a single web positioning bar can be used either on one side or the other of the web, depending uppon the change in direction desired. A single bar may be used in a dryer between adjacent banks of nozzles to minimize utter of the web as it passes through the dryer (see FIG. l).

The `source of pressurized air and the web positioning mechanism are constructed and arranged so as to produce a pressure adequate to stabilize the moving web at a relatively xed distance -from the deector means. In one present form of the invention, the fan will produce three pounds per square inch gauge pressure in the system. Since the air streams issuing from the nozzle-like openings 42 and 44 in the deflector means are directed toward one another, a region of high turbuelnce results in the region `46. It has been found by this arrangement that there is virtually no force tending to move the web laterally of its line of travel. It will be apparent that any lateral movement of the web from its line of travel would be undesirable for it may result in misalignment of the moving web within the dryer mechanism and possibly result in damage to the web.

By means of the present invention, it is possible t0 guide rapidly moving webs of relatively long length on an air barrier without either opposed surface of the moving web coming into contact with a physical member that would tend to smear the wet ink carried on opposed sides thereof.

We claim:

1. Web positioning mechanism comprising an elongated tubular housing having a pair of spaced elongated opening means in one side thereof, means for introducing pressurized air into said housing for discharge from said opening means, and detiector means secured to the housing for directing the air stream discharging from each opening means toward one another to provide a pressurized air barrier capable of supporting a moving web in spaced relationship to said housing, said housing including separate chambers communicated to a source of pressurized air via an inlet, the outlet from each chamber comprising said opening means.

2. Web positioning mechanism as in claim 1 wherein said detlector means comprises cooperating pairs of elongated plate members substantially coextensive with each of said opening means, the plate members of each pair being disposed in closely spaced relationship at each side of an associated opening means to direct a stream of pressurized air at an acute angle with respect to said one side of the housing, the air streams being directed from the opening means in converging relationship.

3. Web positioning mechanism as in claim 2 wherein the innermost plate member of each pair is disposed at an angle of about 30 with respect to the said one side of the housing and the outermost plate member of each pair is disposed at an angle of about 45 with respect to the said one side of the housing.

4. Web positioning mechanism as in claim 2 wherein means are provided for adjusting the spacing between ad- -5 jacent plate members to thereby control the velocity of discharging air.

5. Web positioning mechanism as in claim 1 wherein the opening means are each dened by continuous slotlike openings.

6. Web positioning mechanism as in claim 1 wherein 5 the moving web is bent over the mechanism in use so as to stabilize the web.

References Cited UNITED STATES PATENTS 3,181,250 5/1965 Vits 34-156X FOREIGN PATENTS 9/ 1964 Great Britain.

ALLEN N. KNOWLES, Primary Examiner.

R. A. SCHACHER, Assistant Examiner.

U.S. C1. X.R. 

